Seung Sik Choi

Learn More
PURPOSE To investigate whether and how insulin-like growth factor 1 (IGF-1) mitigates hematopoietic toxicity after total body irradiation. METHODS AND MATERIALS BALB/c mice were irradiated with a lethal dose of radiation (7.5 Gy) and treated with IGF-1 at a dose of 100 μg/dose intravenously once a day for 5 consecutive days starting within 1 hour after(More)
We propose a coordinated resource allocation(CRA) scheme that can be used to allocate high data-rate users in sectorized cells. This scheme is useful for allocating high data-rate users at cell boundaries. In order to analyze the performance of the proposed scheme, we make an interference model for a sectorized CDMA system and suggest the system load(More)
—Wireless sensor networks consist of sensor nodes which are expected to be battery-powered and are hard to replace or recharge. Thus, reducing the energy consumption of sensor nodes is an important design consideration in wireless sensor networks. For the implementation of an energy-efficient MAC protocol, a Sensor-MAC based on the IEEE 802.11 protocol,(More)
We developed a reliable mobile Peer-to-Peer (P2P) data sharing system and performed some experiments for verifying our routing scheme using our real testbed. Our method for guaranteeing reliable P2P data sharing mainly deals with the problem of disconnection due to the sudden disappearance of one or more nodes involved in the active transmission route. The(More)
A Fair Queueing Algorithm is proposed for data services in an integrated voice/data CDMA system. We introduce short-term and long-term fairness concepts to allocate data users fairly. Using these concepts, we propose Weighted Fair Queueing with Status Control(WFQS) in the consideration of a Generalized Processor Sharing(GPS) ¤uid-¤ow model. This proposed(More)
In this paper, a low latency MAC protocol that can be used in sensor networks is proposed. To extend the lifetime of sensor nodes, it was used to synchronize active/sleep periods of all sensor nodes. However, due to these synchronized sensor nodes, packets in the intermediate nodes must wait until the next node wakes up before it can forward a packet. This(More)